66 research outputs found
Neural regulation of cancer: from mechanobiology to inflammation.
Despite recent progress in cancer research, the exact nature of malignant transformation and its progression is still not fully understood. Particularly metastasis, which accounts for most cancer death, is a very complex process, and new treatment strategies require a more comprehensive understanding of underlying regulatory mechanisms. Recently, the sympathetic nervous system (SNS) has been implicated in cancer progression and beta-blockers have been identified as a novel strategy to limit metastasis. This review discusses evidence that SNS signaling regulates metastasis by modulating the physical characteristics of tumor cells, tumor-associated immune cells and the extracellular matrix (ECM). Altered mechanotype is an emerging hallmark of cancer cells that is linked to invasive phenotype and treatment resistance. Mechanotype also influences crosstalk between tumor cells and their environment, and may thus have a critical role in cancer progression. First, we discuss how neural signaling regulates metastasis and how SNS signaling regulates both biochemical and mechanical properties of tumor cells, immune cells and the ECM. We then review our current knowledge of the mechanobiology of cancer with a focus on metastasis. Next, we discuss links between SNS activity and tumor-associated inflammation, the mechanical properties of immune cells, and how the physical properties of the ECM regulate cancer and metastasis. Finally, we discuss the potential for clinical translation of our knowledge of cancer mechanobiology to improve diagnosis and treatment
A Microfluidic Approach to Encapsulate Living Cells in Uniform Alginate Hydrogel Microparticles
A large displacement, high frequency, underwater microelectromechanical systems actuator
Here, we demonstrate an in situ electrostatic actuator that can operate underwater across a wide range of displacements and frequencies, achieving a displacement of approximately 10-ÎĽm at 500-Hz and 1-ÎĽm at 5-kHz; this performance surpasses that of existing underwater physical actuators. To attain these large displacements at such high speeds, we optimized critical design parameters using a computationally efficient description of the physics of low quality (Q) factor underwater electrostatic actuators. Our theoretical model accurately predicts actuator motion profiles as well as limits of bandwidth and displacement
Nuclear Envelope Composition Determines The Ability Of Neutrophil-Type Cells To Passage Through Micron-Scale Constrictions
Neutrophils are characterized by their distinct nuclear shape, which is thought to facilitate the transit of these cells through pore spaces less than one-fifth of their diameter. We used human promyelocytic leukemia (HL-60) cells as a model system to investigate the effect of nuclear shape in whole cell deformability. We probed neutrophil-differentiated HL-60 cells lacking expression of lamin B receptor, which fail to develop lobulated nuclei during granulopoiesis and present an in vitro model for Pelger-Huët anomaly; despite the circular morphology of their nuclei, the cells passed through micron-scale constrictions on similar timescales as scrambled controls. We then investigated the unique nuclear envelope composition of neutrophil-differentiated HL-60 cells, which may also impact their deformability; although lamin A is typically down-regulated during granulopoiesis, we genetically modified HL-60 cells to generate a subpopulation of cells with well defined levels of ectopic lamin A. The lamin A-overexpressing neutrophil-type cells showed similar functional characteristics as the mock controls, but they had an impaired ability to pass through micron-scale constrictions. Our results suggest that levels of lamin A have a marked effect on the ability of neutrophils to passage through micron-scale constrictions, whereas the unusual multilobed shape of the neutrophil nucleus is less essential
Microfluidics: reframing biological enquiry
The underlying physical properties of microfluidic tools have led to new biological insights through the development of microsystems that can manipulate, mimic and measure biology at a resolution that has not been possible with macroscale tools. Microsystems readily handle sub-microlitre volumes, precisely route predictable laminar fluid flows and match both perturbations and measurements to the length scales and timescales of biological systems. The advent of fabrication techniques that do not require highly specialized engineering facilities is fuelling the broad dissemination of microfluidic systems and their adaptation to specific biological questions. We describe how our understanding of molecular and cell biology is being and will continue to be advanced by precision microfluidic approaches and posit that microfluidic tools - in conjunction with advanced imaging, bioinformatics and molecular biology approaches - will transform biology into a precision science
The molecules we eat: food as a medium to communicate science
Abstract Creative, inquiry-driven approaches in science education help to address the growing need to effectively engage students and promote the public understanding of science. Here we describe an interactive format using food that can be applied both in a course for undergraduate students, as well as in a lecture for the general public. Communicating science through food may also dispel fear of naturally occurring chemicals as well as scientific misconceptions that are propagated by the media
Farnesol-DMPC phase behaviour: a 2H-NMR study
AbstractInvolved in a number of diverse metabolic and functional contexts, farnesol is a central component of the mevalonate pathway, post-translationally attaches to proteins, and affects a number of other membrane-associated events. Despite farnesol's biological implications, a detailed analysis of how farnesol affects the physical properties and phase behaviour of lipid membranes is lacking. As 2H-NMR spectra are sensitive to molecular motions and acyl chain orientation, they can be used to measure the degree of molecular order present in the system. Also, since the 2H-NMR spectra of fluid and gel phase lipids are very different, they are sensitive probes of membrane phase equilibrium and can be used to determine fluid–gel phase boundaries. In this study, dimyristoyl phosphatidylcholine-d54 (DMPC-d54) bilayers containing varying concentrations of trans–trans farnesol (2.5–20.0 mol%) are investigated over a range of temperatures (8–30 °C). Analysis of these spectra has led to the construction of a farnesol-DMPC-d54 temperature–composition plot. We show that increasing concentrations of farnesol induce a decrease in the fluid–gel phase transition temperature and promote fluid–gel coexistence. Interestingly, farnesol does not seem to affect the quadrupolar splittings (ΔvQ) in the fluid phase, i.e., the organization of farnesol within the bilayer and its interaction with phospholipids does not appreciably influence acyl chain order in the fluid phase
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